Pliable toy compositions for the entertainment of children which consist of bulk blocks or globs of molding material have been available for many years. The consistency of these toys has ranged from modeling clay for making sculptures and models to slimy gels which children may squeeze and stretch.
Modeling clay consists of a very firm, but deformable putty material which will hold its shape while the sculptor forms or carves figures of animals, people, or structures. The attributes of clay putties are derived from the fine particulate clays held in a matrix by various nonaqueous binders. Particulate clay matter comprises a major percentage of the composition of clay putties. While modeling clay is useful in applications requiring a formable substance capable of retaining a shape, modeling clay lacks the degree of elasticity, coherence, and dilatency present in more pliable compositions.
In addition, clay particles block the passage of light through the composition, thereby preventing the attribution of any phosphorescent character which might be desired in the clay.
Pliable toy compositions which are slightly more soft and tractable than clay are often referred to as doughs. Doughs can be extruded through dies into long ropes or rolled into flat cakes which can be cut with "cookie cutters." These products tend to dry out very quickly and like clay putties, do not exhibit the degree of elasticity, coherence and dilatency provided by more pliable compositions.
An even more pliable toy composition is often referred to as a "gel. " Gel compositions are aqueous compositions thickened with gums, starches, resins or fine silica. The rheology of the composition may vary widely depending on the thickening agents used and the additives present.